Let-off mechanism for looms



- (No Model.)

1\I.' r.1 -0LSOM.y LET-OPP MBCHANISM FOR LOOMS.

,Patented June 23, 1896.`

WTNEESES:

JJ #Mad/w.

UNITED STATES PATENT OFFICE.

NEI-IEMIAH T. FOLSOM, OF MANCHESTER, NEW HAMPSHIRE, ASSIGNOR OF ONEHALF TO JOHN S. FOLSOM, OF MILLIS, MASSACHUSETTS.

LET-OFF MEcHANlsM FOR Loolvls.

SPECIFICATION forming part of Letters Patent No. 562,598, dated .Tune 23,` 1896.

` Application mea March 21,1896. serial No. 584,240. (No moana To aZZ whom it may concern.-

Be it known that I, NEHEMIAH T. FoLsOM, of Manchester, in the countyT of Hillsborough and State of New Hampshire, have invented certain new and useful Improvements in Let- Off Mechanism for Looms, of which the following is a specification.

rlhis invention relates to appliances designed to vary the resistance to the unwinding of the warp from the warp-beam of a loom according to the decrease in diameter as the warp unwinds.

In my application for Letters Patent of the United States iiled October 14C, 1895, Serial No. 565,568, I showa let-off mechanism comprising a lever pivoted at one end to the frame of the machine under the warp-beam and having an upward inclination, a brake-strap connected at one end to the frame of the machine and at the other end to the said lever near its pivot, said brale-strap winding on a pulley on the warpbeam, a weight embracing the inelined part of the lever and adapted to slide on the same, and having a rigid upstanding arm, and a shoe on said arm adapted to be pressed against the roll of warp by the down ward tendency of the weight on the lever.

My present invention has for its object to prevent the inconvenience caused by the projection of the said lever outside of the warpbeam, particularly when the warp-beam is nearly empty, the outer end of the lever being farther from the periphery of the accumulation of warp upon the beam when the beam is nearly empty than when it is full.

rlhe invention consists in a letoff mechanism comprising the general features set forth in the former application above referred to, with the following difference, namely, the weight, instead of sliding on a lever which is pivoted to the frame of the loom, and has no endwise movement, is affixed to a bar or lever` which slides with the weight in a lever-head which is pivoted to the frame of the machine and has a guide or slot in which the weighted leveris movable endwise, so that as the weight moves inwardly the lever moves with it and does not project outside of the accumulation of warp when the beam is comparatively empty any farther than when the beam is full.

Of the accompanying drawings, forming a `part of this specificatiomliigure l represents a side elevation of my improved let-off mechan ism, the warp-beam being shown in section. Fig. 2 represents a front elevation. Fig. 3 represents a section on line 3 3 of Fig. l.

In the drawings, a represents the warpbeam; b,the accumulation of warp thereon; c, the frame of the loom, and d'the disk or pulley afIiXed to one end of the warp-beam.

e represents a lever-head, which is pivoted to the frame of the machine, preferably by means of a socket e2, formed on said head, and a stud es, affixed to the loom-frame and entering said socket, the head being adapted to oscillate in a vertical plane. The head c is located under the warp-beam, and in close proximity thereto, as shown in Fig. 1, and is provided with a guide or slot e4, Fig. 3, which extends through it, below the pivot or stud es. l f represents a brake-strap, which is wound several times about the pulley d, and is fastened at one end to the frame of the machineat f', and at the other end to the lever-head e at f2, said strap being arranged to hold the lever-head with its slot or guide e4 in an inclined position.

g represents a weight, which is secured to one end of a bar or lever e., and has an upwardly-projecting arm g', the upper end of which is engaged with ears h h on a shoe h', adapted to bear against the accumulation of warp b, said arm being rigidly attached to the weight g, so that it cannot swing independently. The bar or lever e is fitted to slide in the slot or guide e4 ofthe lever-head, and is adapted by the inclination of said slot or guide to move by gravitation in the direction required to carry the shoe h toward the axis of the warp-beam.

It will be seen that as the accumulation of warp decreases, the weighted bar or lever c slides inwardly as fast as the shoe h' will permit, the weight g being thus moved toward the pivot of the lever-head, as the diameter of the roll lessens. Hence the tension exerted IQO face of the accumulation of Warp, the lever receding With the Weight, so that it projects no farther from the Warp When the beam is comparatively empty than When the beam is full.

The strap f may be connected at both ends to the lever-head, as shown in Fig. 4, instead.

of being connected at one end to the frame.

I claim- A let-off mechanism for looms,comprising a lever-head pivoted to the frame of the machine under the Warp-beam and having a longitudinal guide or slot, a brake-strap arranged to hold the head With its guide or slot in an inclined position, said strap encircling a pulley on the Warp-beam, a Weighted bar o1i NEHEMIAH T. FOLSOM. Vitnesses:

C. F. BROWN, A. D. HARRISON. 

